parse_yn00(lines,
results,
sequences)

Parse the Yang & Nielsen (2000) part of the results.
Yang & Nielsen results are organized in a table with
each row comprising one pairwise species comparison.
Rows are labeled by spequence number rather than by
sequence name.

parse_others(lines,
results,
sequences)

Parse the results from the other methods.
The remaining methods are grouped together. Statistics
for all three are listed for each of the pairwise
species comparisons, with each method's results on its
own line.
The stats in this section must be handled differently
due to the possible presence of NaN values, which won't
get caught by my typical "line_floats" method used above.